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Subject: Re: Create a spaced vector for a log-plot
Date: Sun, 29 Apr 2012 16:53:07 +0000 (UTC)
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dpb <none@non.net> wrote in message <jnjiln$q5u$1@speranza.aioe.org>...
> On 4/28/2012 6:45 PM, Roger Stafford wrote:
> ...
> 
> > Hermano, you should realize that the spacing you have requested is not
> > in any sense a "log-spaced vector" because the ratio between successive
> > interval lengths is not held constant. From .1 to 1 the intervals are
> > all the same length and then suddenly the length is multiplied by 10.
> > The intervals are then constant again until 100, at which time they are
> > again multiplied by 10, etc. This irregularity could lead to a
> > misinterpretation of displayed data.
> 
> I figured he was looking to label ticks specifically; if so when he 
> switches/sets to log axes the spacing between the ticks will be set for 
> him automagically.
> 
> Certainly the values aren't logrithmically spaced numerically, that's as 
> OP noted what he gets if uses logspace() but they're "clean" for 
> presentation purposes and if the data are spaced over a reasonable 
> number of decades and plot size w/ font chosen appropriately, probably 
> makes for a decent-looking plot.
> 
> --

Indeed, dpb, the reason why I want to use this sequence of "log-spaced" values (indeed it is not a really log-spaced vector as Roger says) is only for a clean presentation in a log plot.